In radio communications systems such as, for example, those in the microwave frequency range, in particular in so called star shaped systems, i.e. systems with a number of point to point paths to a central node, it is difficult to achieve a sufficient degree of isolation between the different paths so as to reduce the degree of interference between the paths to an acceptable level. One known way of reducing inter-path interference in a star shaped system is to use a large frequency separation between the paths. This is however not desirable, since frequency reuse is highly desirable, i.e. it is desired to use the same frequencies in the system as much as possible.
Another known way of reducing inter-path interference is to use so called “node cancellation”, i.e. to let a receiver which has a high degree of interference from adjacent paths include a cancellation circuit which receives information from the receivers of the interfering paths, and which uses this information together with the signal received by the “own” receiver in order to cancel interference, for example by comparing the signal received by the own receiver with the signal or signals received by the receivers of the interfering paths.